Local, state officials want cleaner water in Malibu Creek





By John Loesing
Acorn Staff Writer

The season’s first rain fell two weeks ago. It swelled the local creeks and purged months of stagnated water from the Malibu Creek watershed.


In addition to the start of the rainy season, November also marks the beginning of a five-month period each year when the Tapia Water Reclamation Facility in Calabasas is permitted to discharge its excess reclaimed sewer water into Malibu Creek.


Releasing recycled water into the creek during the dry spring and summer months–when the torpid waterways are susceptible to pollution–might break the natural sand berm at Malibu Lagoon and pour pollutants into popular Surfrider Beach, according to environmentalists and state water officials.


Tapia’s water also is banned from the creek during the dry season because it could cause algae growth that’s harmful to fish and wildlife.


With Tapia’s five-year operating permit up for renewal at the end of the year, the state Regional Water Quality Control Board hinted that it would impose strict new regulations governing the amount of algae-causing nitrogen and other compounds commonly found in reclaimed water.


The permit currently is under review.


Tapia’s existing permit calls for a reduction in nitrogen to 10 milligrams per liter in the treated sewer water, but Las Virgenes Municipal Water District (LVMWD) officials say that new permit requirements could drop the level as low as 2.5 milligrams.


The state also intends to limit the amount of other harmful nutrients Tapia is allowed to put into the creek, such as phosphorous.


Too much bacteria in the creek can be a problem, too, the state board says. The bacteria come not only from humans, but from wild animals and livestock.


Nutrients—nitrates and phosphates—are inherent in all recycled water, according to scientists. And while the debate continues as to what levels actually constitute a danger, LVMWD officials complain that they’re forced to spend about $500,000 in taxpayer money each year to divert the excess water away from the creek.


The structural and operational changes needed to bring Tapia in line with the new regulations could cost as much as $80 million, according to a water district consultant.


LVMWD, which has operated the Tapia plant since 1965, believes the state’s demands for lower nutrient levels are unreasonable because algae has been shown to thrive in the creek even before the recycled water is added.


"The 2.5 milligrams for nitrate wasn’t really based on local science," said Randal Orton, LVMWD’s resource conservation administrator. "There’s federal guidance out there for nutrients that the EPA (Environmental Protection Agency) has come up with and most of that guidance was developed for East Coast lakes and streams, which are much different that we’ve got here."


Studies show that the Malibu Creek algae growth is more a function of slow stream velocity and low sunlight rather than nitrate levels, the water district stated in a recent position paper concerning its Tapia permit.


State officials say they still have concerns.


Because of the amount of nearby urban development, Malibu Creek has become one of the most environmentally sensitive watersheds in Southern California.


"The 2 [level] is what we need to meet these water quality standards in that watershed," said Melinda Becker, a spokeswoman for the state.


While the two sides may be split apart on the nutrient levels, they agree that the ammonia content in Tapia’s water is safe.


Tapia takes most of the ammonia from the sewage and converts it into harmless atmospheric nitrogen through a process called nitrification.


"We have virtually undetectable levels of ammonia in our effluent," Orton said. "That’s very hard to do."


"They’re doing very well in the ammonia," Becker said. "There’s no (ammonia) toxicity in Malibu Creek."


But Becker warned that the other pollutants will remain under scrutiny as the permit process continues.


LVMWD officials, meanwhile, fear the worst if the demands placed on Tapia are too high.


"My concern is if they change the effluent levels, we’ll be in a lawsuit with them," said Glen Peterson, LVMWD boardmember.



Leave a Reply

Your email address will not be published. Required fields are marked *